Device for retarding and for regulating the speed of the flow in accordions and similar musical reed instruments



Jan. 13, 1948. R. SEYBOLD 2,434,441

DEVICE FOR RETARDING AND FOR REGULATING THE SPEED OF THE FLOW INACCORDIONS AND SIMILAR MUSICAL REED INSTRUMENTS Filed May 22, 1940Patented Jan. 13, 1948 DEVICE FOR RETARDING AND FOR REGU LATING THESPEED OF THE FLOW IN AC-. CORDIONS AND SIMILAR MUSICAL REED INSTRUMENTSRene Seybold, Strasbourg -Meinau, France Application May 22, 1940,Serial No, 336,566 In France June 13, 1939,

Section 3, Public Law 690, August 8, 1946 Patent expires June 13, 1959Claims. 1

This invention relates to the art of -making devices for retarding andregulating the speed of the. flow in accordions and similar musicalreedinstruments by inserting two or more elastic and rigid compartmentscommunicating through narrow perforations, or pipes and by the aid ofwhich the regulating of the speed of the flow may be secured.

The sound of musical reed-instruments with key-boards, whatever shapeand denomination might have been given to these instruments, areproduced by the aid of well tuned metallic reeds without head-pieces.These reeds are called free reeds and in contrast to the soft cane-reedstops of the orchestra-instruments are capable of oscillating in theirown period. They are brought into oscillation by the difierence of theatmospheric pressure on their respective sides. The air flows inconsequence periodically through the openings in which the reeds arefixed, in the direction of the lower pressure.

It is known that the timbre is influenced by all the details of themechanical fabrication ofthe.

reeds as well as by the fixation of the latter on the opening over whichit is fitted up. But both the character of its excitement and itsposition with respect to the blowing-in current are decisive of. thenature of the formation of the sounds. The excitement of metallic reedsin key-instruments is brought about, in contradistinction to theorchestra-instruments provided with soft cane-reeds, by air producedmechanically, namely by one or more collapsible bellows the dimensionsof which are fixed by the wind-consumption of the totality of the tunes.

Two distinct species are known:

In the case of organs as well as in similar musical instruments thesound-producers receive their blast from a blast-engine capable ofdeliverlng an air-current of unlimited duration, and the tension ofwhich remains constantly uniform. Neither the tension nor the speed ofthe flow can be influenced by the player; the sound-producers areintonated for a fixed blast, i. e., they are so regulated that theyclearly and fully accept and deliver for a fixed speed of the flow.

Now, contrarily to the production of blast in the organ-likeinstruments, the excitement of the metallic reeds in musical instrumentsbelonging to the class of accordions is brought about by the aid of agradual increase of the air coming in or flowing out from collapsiblequadrangular air bellows. The bellows have neither suction-valves nordischarge-valves; when the bellows are extended, atmospheric air issucked into the same 2 through the exposed openingsofthe reeds, and thedrawn-in air is thereafter expelled through these openings due to thecompression of the bellows.

As oftenas the openings are shut or exposed by the key-valves the flowof air through the accordion'receives a more or'less hard blow, i. e., asudden compression or expansion takes place influencing the volume ofthe bellows and bringing about the well known hard, hacking sound of theaccordion.

In order to make the reed-instruments of the accordion type suitable forperformance of serious music, the present inventionprovides-certaindamming or retarding means, whereby the compressionandflow of air is broughtunderthe control of the player. Thus, it ispossible to produce a musical tone with all the expressiveness andartistry as is produced by the customary artists instruments namely,string and wind-instruments. As is well known these phenomena are due tothe compound vibration which may be produced-on these-instruments.

The accompanyingdrawing-illustrates but does not limit themeansemployedfor carrying out the principle ofcompound acoustic control in-the caseofaccordions.

The drawing represents a cross-section-through an accordion.

In the drawing reference characters I, la designate the checks orretarding means for shutting up the open ends of the collapsible bellows2 thus forming three compartments 3, 4, 4a. Reference characters 5, 5arepresent the check-nozzles. 6, 6a are the reed-chambers, 1, 1arepresent the openings of the reed-chambers, while 8, 8a designate theframes of the reeds and 9, 9a represent the reeds proper; the key-valvesare designated by ID, Illa, the bass-part is represented by H and thesoprano-part is designated by It is known that in the case of accordionsthe bass-part H and the soprano-part shut up both to the air pressure.According to the present invention, on the other hand, two or morecompartments are formed instead of a single main compartment. Theseveral compartments differ in that variable pressures are produced inone of the compartments 3 which pressures are brought about byincreasing or reducing the volume whereas the other compartments 4, 4aserve for producing the compound sound efiect referred to above.

When the compartment 3 is first extended and then compressed, acompression, corresponding to the applied force, of the air-volumecomprised in this compartment takes place at once. A quantity of aircorresponding to the cross-section of the check-nozzles 5, 5a flows intothese nozzles, but the air current is here retarded or dammed over acertain distance. Thereafter the air fills the compartments 4, 4a andfinally enters the reed-chambers 5, 6a.

Now, when the key-valve I exposes the opening 1 the vibration of thereed 9 in the direction of lower pressure takes place; in thecompartment 3 or rather in the check-nozzles 5, the escape of the air isthen retarded as often as the reed 9 closes the frame of the reed. Ifthe compartment 4 has been given adequate dimensions, a compression-waveis produced therein which enhances the natural vibrations of the reed.

As soon as the pressure is increased in the compart 3 the resistance inthe check-nozzles 3 becomes greater, the speed of the flow increasesaccordingly so that the amplitude of oscillation of the reed undergoesan enlargement equal to the resting-position; in the case of adiminution of the pressure the speed of the air current is reduced inthe reverse direction till the tone slowly dies out.

The smaller the set of reeds the more efficient is the retardation. Thenumber of the compartments 4 may therefore be increased in acorresponding manner. Each set of reeds receives the current of acertain number of check-nozzles corresponding to the air currentconsumed thereby.

What I claim is:

1. An accordion comprising two compartments,

one of said compartments being elastic and the other rigid, and soundproducing means in said rigid compartment, said means being adapted toproduce musical sounds when air under pressure is admitted to the rigidcompartment, a wall separating said two compartments, said wall havingperforations to establish communication between said comparments,whereby regulation of the speed of the flow of air is secured, thenumber of said perforations corresponds in each case to the amount ofair consumed, between the elastic compartment and the rigid compartment,the air compressed in the elastic compartment is driven through saidperforations and delayed for a certain length before it flows into therigid compartment.

2. The device claimed in claim 1, comprising a second wall to form threecompartments, said second wall having perforations whereby communicationbetween said three compartments is established, and said elasticcompartment is formed by collapsible bellows, and the remaining twocompartments forming the bass part and the soprano part, respectively,said two walls being disposed between the bass-parts, the bellows andthe soprano-parts.

3. The device claimed in claim 1, in which nozzles or pipes extendthrough said perforations, said nozzles or pipes having an unequalwidth.

4. The device claimed in claim 1, in which said sound producing meansare formed by reeds, said reeds being subdivided and disposed insub-compartments wherein the volume of the tone of the reeds is severaltimes divided each sub-compartment being provided with perforations, a,number of nozzles disposed in said perforations, the number of saidnozzles corresponding to the capacity of each compartment.

5. The device claimed in claim 1, comprising a plurality of stop-valvesin said rigid compartment adapted to selectively close certain of saidperforations according to the consumption of air and the desired volumeof the tone.

RENE SEYBOLD.

UNITED STATES PATENTS Number Name Date 1,139,010 Anderson May 11, 1915FOREIGN PATENTS Number Country Date 31,010 Germany Apr. 18, 1885

